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1.
Nature ; 585(7823): 96-101, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32814898

RESUMO

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are neurodegenerative disorders that overlap in their clinical presentation, pathology and genetic origin. Autoimmune disorders are also overrepresented in both ALS and FTD, but this remains an unexplained epidemiologic observation1-3. Expansions of a hexanucleotide repeat (GGGGCC) in the C9orf72 gene are the most common cause of familial ALS and FTD (C9-ALS/FTD), and lead to both repeat-containing RNA and dipeptide accumulation, coupled with decreased C9orf72 protein expression in brain and peripheral blood cells4-6. Here we show in mice that loss of C9orf72 from myeloid cells alone is sufficient to recapitulate the age-dependent lymphoid hypertrophy and autoinflammation seen in animals with a complete knockout of C9orf72. Dendritic cells isolated from C9orf72-/- mice show marked early activation of the type I interferon response, and C9orf72-/- myeloid cells are selectively hyperresponsive to activators of the stimulator of interferon genes (STING) protein-a key regulator of the innate immune response to cytosolic DNA. Degradation of STING through the autolysosomal pathway is diminished in C9orf72-/- myeloid cells, and blocking STING suppresses hyperactive type I interferon responses in C9orf72-/- immune cells as well as splenomegaly and inflammation in C9orf72-/- mice. Moreover, mice lacking one or both copies of C9orf72 are more susceptible to experimental autoimmune encephalitis, mirroring the susceptibility to autoimmune diseases seen in people with C9-ALS/FTD. Finally, blood-derived macrophages, whole blood and brain tissue from patients with C9-ALS/FTD all show an elevated type I interferon signature compared with samples from people with sporadic ALS/FTD; this increased interferon response can be suppressed with a STING inhibitor. Collectively, our results suggest that patients with C9-ALS/FTD have an altered immunophenotype because their reduced levels of C9orf72 cannot suppress the inflammation mediated by the induction of type I interferons by STING.


Assuntos
Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Inflamação/metabolismo , Inflamação/prevenção & controle , Proteínas de Membrana/metabolismo , Células Mieloides/metabolismo , Envelhecimento/imunologia , Esclerose Amiotrófica Lateral/genética , Animais , Proteína C9orf72/deficiência , Células Dendríticas/citologia , Células Dendríticas/imunologia , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Feminino , Humanos , Inflamação/genética , Inflamação/imunologia , Interferon Tipo I/biossíntese , Interferon Tipo I/imunologia , Proteínas de Membrana/antagonistas & inibidores , Camundongos , Células Mieloides/imunologia , Neoplasias/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia
2.
Nature ; 584(7822): 624-629, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32788723

RESUMO

Conventional type 1 dendritic cells (cDC1)1 are thought to perform antigen cross-presentation, which is required to prime CD8+ T cells2,3, whereas cDC2 are specialized for priming CD4+ T cells4,5. CD4+ T cells are also considered to help CD8+ T cell responses through a variety of mechanisms6-11, including a process whereby CD4+ T cells 'license' cDC1 for CD8+ T cell priming12. However, this model has not been directly tested in vivo or in the setting of help-dependent tumour rejection. Here we generated an Xcr1Cre mouse strain to evaluate the cellular interactions that mediate tumour rejection in a model requiring CD4+ and CD8+ T cells. As expected, tumour rejection required cDC1 and CD8+ T cell priming required the expression of major histocompatibility class I molecules by cDC1. Unexpectedly, early priming of CD4+ T cells against tumour-derived antigens also required cDC1, and this was not simply because they transport antigens to lymph nodes for processing by cDC2, as selective deletion of major histocompatibility class II molecules in cDC1 also prevented early CD4+ T cell priming. Furthermore, deletion of either major histocompatibility class II or CD40 in cDC1 impaired tumour rejection, consistent with a role for cognate CD4+ T cell interactions and CD40 signalling in cDC1 licensing. Finally, CD40 signalling in cDC1 was critical not only for CD8+ T cell priming, but also for initial CD4+ T cell activation. Thus, in the setting of tumour-derived antigens, cDC1 function as an autonomous platform capable of antigen processing and priming for both CD4+ and CD8+ T cells and of the direct orchestration of their cross-talk that is required for optimal anti-tumour immunity.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Apresentação Cruzada , Células Dendríticas/imunologia , Neoplasias/imunologia , Animais , Apresentação do Antígeno/imunologia , Linfócitos T CD4-Positivos/citologia , Antígenos CD40/imunologia , Antígenos CD40/metabolismo , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Feminino , Antígenos de Histocompatibilidade Classe II/imunologia , Camundongos , Transdução de Sinais
3.
PLoS One ; 15(7): e0230835, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32701966

RESUMO

Syndecan-1 (Sdc-1) is a heparan sulfate proteoglycan that can bind cytokines and chemokines via its heparan sulfate side chains, and has immunomodulatory properties in experimental models. Sdc-1 expression has been reported on dendritic cells (DC) and T cells. The potential role of Sdc-1 in DC-T cell interaction has not been investigated yet. We postulate that Sdc-1 is involved in DC-T cell interaction and may influence graft survival in an allogeneic transplant model. Sdc-1 expression on bone marrow-derived DC and T cells was analyzed by flow cytometry. Unstimulated and LPS stimulated Sdc-1 deficient DC were evaluated in vitro for phenotype and stimulatory capacity in mixed lymphocyte reaction. Sdc-1 deficient T cells were evaluated for proliferative capacity and differentiation in a mixed lymphocyte reaction and a proliferation assay. Allograft survival was evaluated in a fully MHC mismatched heterotopic heart transplant model, with either Sdc-1 deficient donors or recipients. Sdc-1 was expressed on the cell surface of unstimulated and LPS matured DC. Sdc-1 deficiency had no effect on expression of co-stimulatory molecules, cytokine production or T cell stimulatory capacity as compared to WT DC. Sdc-1 expression was not detectable on WT T cells, although intracellular Sdc-1 expression could be demonstrated after ConA activation. Sdc-1 deficient T cells showed reduced proliferation upon DC or ConA stimulation and reduced IL-17 production upon ConA stimulation, compared to WT T cells. Sdc-1 deficiency of either allograft or recipient did not prolong allograft survival. In conclusion, Sdc-1 is expressed on the cell surface of DC, where its absence does not affect DC phenotype or T cell stimulatory capacity. Sdc-1 is intracellularly expressed in ConA activated T cells. Sdc-1 deficiency in T cells results in a reduced proliferative response in vitro, as induced by DC and ConA. Sdc-1 deficiency in donor or recipient does not affect allograft survival.


Assuntos
Comunicação Celular , Células Dendríticas/citologia , Sindecana-1/metabolismo , Linfócitos T/citologia , Animais , Proliferação de Células , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo
4.
PLoS One ; 15(7): e0232307, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667911

RESUMO

In the mammalian gut CD103+ve myeloid DCs are known to suppress inflammation threatened by luminal bacteria, but stimuli driving DC precursor maturation towards this beneficial phenotype are incompletely understood. We isolated CD11+ve DCs from mesenteric lymph nodes (MLNs) of healthy mice; CD103+ve DCs were 8-24 fold more likely than CD103-ve DCs to exhibit extensive of prior phagocytosis of apoptotic intestinal epithelial cells. However, CD103+ve and CD103-ve MLN DCs exhibited similar ex vivo capacity to ingest apoptotic cells, indicating that apoptotic cells might drive immature DC maturation towards the CD103+ve phenotype. When cultured with apoptotic cells, myeloid DC precursors isolated from murine bone marrow and characterised as lineage-ve CD103-ve, displayed enhanced expression of CD103 and ß8 integrin and acquired increased capacity to induce T regulatory lymphocytes (Tregs) after 7d in vitro. However, DC precursors isolated from αv-tie2 mice lacking αv integrins in the myeloid line exhibited reduced binding of apoptotic cells and complete deficiency in the capacity of apoptotic cells and/or latent TGF-ß1 to enhance CD103 expression in culture, whereas active TGF-ß1 increased DC precursor CD103 expression irrespective of αv expression. Fluorescence microscopy revealed clustering of αv integrin chains and latent TGF-ß1 at points of contact between DC precursors and apoptotic cells. We conclude that myeloid DC precursors can deploy αv integrin to orchestrate binding of apoptotic cells, activation of latent TGF-ß1 and acquisition of the immunoregulatory CD103+ve ß8+ve DC phenotype. This implies that a hitherto unrecognised consequence of apoptotic cell interaction with myeloid phagocytes is programming that prevents inflammation.


Assuntos
Antígenos CD/metabolismo , Apoptose , Células Dendríticas/imunologia , Regulação da Expressão Gênica , Imunomodulação , Cadeias alfa de Integrinas/metabolismo , Integrina alfaV/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Feminino , Camundongos Endogâmicos C57BL , Células Mieloides/citologia , Fagocitose , Linfócitos T Reguladores/imunologia
5.
Proc Natl Acad Sci U S A ; 117(29): 17041-17048, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32632001

RESUMO

A central task in developmental biology is to learn the sequence of fate decisions that leads to each mature cell type in a tissue or organism. Recently, clonal labeling of cells using DNA barcodes has emerged as a powerful approach for identifying cells that share a common ancestry of fate decisions. Here we explore the idea that stochasticity of cell fate choice during tissue development could be harnessed to read out lineage relationships after a single step of clonal barcoding. By considering a generalized multitype branching process, we determine the conditions under which the final distribution of barcodes over observed cell types encodes their bona fide lineage relationships. We then propose a method for inferring the order of fate decisions. Our theory predicts a set of symmetries of barcode covariance that serves as a consistency check for the validity of the method. We show that broken symmetries may be used to detect multiple paths of differentiation to the same cell types. We provide computational tools for general use. When applied to barcoding data in hematopoiesis, these tools reconstruct the classical hematopoietic hierarchy and detect couplings between monocytes and dendritic cells and between erythrocytes and basophils that suggest multiple pathways of differentiation for these lineages.


Assuntos
Linhagem da Célula , Código de Barras de DNA Taxonômico/métodos , Animais , Linhagem da Célula/genética , Linhagem da Célula/fisiologia , Árvores de Decisões , Células Dendríticas/citologia , Eritrócitos/citologia , Hematopoese/genética , Hematopoese/fisiologia , Leucócitos/citologia , Modelos Biológicos , Biologia de Sistemas
6.
Int J Nanomedicine ; 15: 4151-4169, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606670

RESUMO

Purpose: Focused ultrasound (FUS) is a noninvasive method to produce thermal and mechanical destruction along with an immune-stimulatory effect against cancer. However, FUS ablation alone appears insufficient to generate consistent antitumor immunity. In this study, a multifunctional nanoparticle was designed to boost FUS-induced immune effects and achieve systemic, long-lasting antitumor immunity, along with imaging and thermal enhancement. Materials and Methods: PEGylated PLGA nanoparticles encapsulating astragalus polysaccharides (APS) and gold nanorods (AuNRs) were constructed by a simple double emulsion method, characterized, and tested for cytotoxicity. The abilities of PA imaging and thermal-synergetic ablation efficiency were analyzed in vitro and in vivo. The immune-synergistic effect on dendritic cell (DC) differentiation in vitro and the immune response in vivo were also evaluated. Results: The obtained APS/AuNR/PLGA-PEG nanoparticles have an average diameter of 255.00±0.1717 nm and an APS-loading efficiency of 54.89±2.07%, demonstrating their PA imaging capability and high biocompatibility both in vitro and in vivo. In addition, the as-prepared nanoparticles achieved a higher necrosis cell rate and induced apoptosis rate in an in vitro cell suspension assay, greater necrosis area and decreased energy efficiency factor (EEF) in an in vivo rabbit liver assay, and remarkable thermal-synergic performance. In particular, the nanoparticles upregulated the expression of MHC-II, CD80 and CD86 on cocultured DCs in vitro, followed by declining phagocytic function and enhanced interleukin (IL)-12 and interferon (INF)-γ production. Furthermore, they boosted the production of tumor necrosis factor (TNF)-α, IFN-γ, IL-4, IL-10, and IgG1 (P< 0.001) but not IgG2a. Immune promotion peaked on day 3 after FUS in vivo. Conclusion: The multifunctional APS/AuNR/PLGA-PEG nanoparticles can serve as an excellent synergistic agent for FUS therapy, facilitating real-time imaging, promoting thermal ablation effects, and boosting FUS-induced immune effects, which have the potential to be used for further clinical FUS treatment.


Assuntos
Astrágalo (Planta)/química , Neoplasias da Mama/terapia , Ouro/química , Nanopartículas Multifuncionais/química , Nanotubos/química , Polissacarídeos/química , Terapia por Ultrassom , Animais , Antígenos CD/metabolismo , Apoptose , Morte Celular , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/metabolismo , Células Dendríticas/citologia , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imunoglobulina G/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Camundongos Endogâmicos BALB C , Fagocitose , Técnicas Fotoacústicas , Poliésteres/síntese química , Poliésteres/química , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Coelhos , Nanomedicina Teranóstica , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Nat Commun ; 11(1): 3366, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632165

RESUMO

CD4+ T lymphocytes consist of naïve, antigen-specific memory, and memory-phenotype (MP) cell compartments at homeostasis. We recently showed that MP cells exert innate-like effector function during host defense, but whether MP CD4+ T cells are functionally heterogeneous and, if so, what signals specify the differentiation of MP cell subpopulations under homeostatic conditions is still unclear. Here we characterize MP lymphocytes as consisting of T-bethigh, T-betlow, and T-bet- subsets, with innate, Th1-like effector activity exclusively associated with T-bethigh cells. We further show that the latter population depends on IL-12 produced by CD8α+ type 1 dendritic cells (DC1) for its differentiation. Finally, our data demonstrate that this tonic IL-12 production requires TLR-MyD88 signaling independent of foreign agonists, and is further enhanced by CD40-CD40L interactions between DC1 and CD4+ T lymphocytes. We propose that optimal differentiation of T-bethigh MP lymphocytes at homeostasis is driven by self-recognition signals at both the DC and Tcell levels.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Homeostase/imunologia , Memória Imunológica/imunologia , Proteínas com Domínio T/imunologia , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD40/imunologia , Antígenos CD40/metabolismo , Ligante de CD40/genética , Ligante de CD40/imunologia , Ligante de CD40/metabolismo , Antígenos CD8/imunologia , Antígenos CD8/metabolismo , Comunicação Celular/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-12/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Transdução de Sinais/imunologia , Proteínas com Domínio T/metabolismo , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo
8.
Mol Immunol ; 124: 190-197, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32593782

RESUMO

Understanding development of the dendritic cell (DC) subtypes continues to evolve. The origin and relationship of conventional DC type 1 (cDC1), cDC type 2 (cDC2) and plasmacytoid DCs (pDCs) to each other, and in relation to classic myeloid and lymphoid cells, has had a long and controversial history and is still not fully resolved. This review summarises the technological developments and findings that have been achieved at a clonal level, and how that has enhanced our knowledge of the process. It summarises the single cell lineage tracing technologies that have emerged, their application in in vitro and in vivo studies, in both mouse and human settings, and places the findings in a wider context of understanding haematopoiesis at a single cell or clonal level. In particular, it addresses the fate heterogeneity observed in many phenotypically defined progenitor subsets and how these findings have led to a departure from the classic ball-and-stick models of haematopoiesis to the emerging continuous model. Prior contradictions in DC development may be reconciled if they are framed within this revised model, where commitment to a lineage or cell type does not occur in an all-or-nothing process in defined progenitors but rather can occur at many stages of haematopoiesis in a dynamic process.


Assuntos
Células Dendríticas/citologia , Hematopoese , Animais , Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Humanos
9.
PLoS One ; 15(6): e0233773, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32559198

RESUMO

In early life and around weaning, pigs are at risk of developing infectious diseases which compromise animal welfare and have major economic consequences for the pig industry. A promising strategy to enhance resistance against infectious diseases is immunomodulation by feed additives. To assess the immune stimulating potential of feed additives in vitro, bone marrow-derived dendritic cells were used. These cells play a central role in the innate and adaptive immune system and are the first cells encountered by antigens that pass the epithelial barrier. Two different feed additives were tested on dendritic cells cultured from fresh and cryopreserved bone marrow cells; a widely used commercial feed additive based on yeast-derived ß-glucans and the gram-negative probiotic strain E. coli Nissle 1917. E. coli Nissle 1917, but not ß-glucans, induced a dose-dependent upregulation of the cell maturation marker CD80/86, whereas both feed additives induced a dose-dependent production of pro- and anti-inflammatory cytokines, including TNFα, IL-1ß, IL-6 and IL-10. Furthermore, E. coli Nissle 1917 consistently induced higher levels of cytokine production than ß-glucans. These immunomodulatory responses could be assessed by fresh as well as cryopreserved in vitro cultured porcine bone marrow-derived dendritic cells. Taken together, these results demonstrate that both ß-glucans and E. coli Nissle 1917 are able to enhance dendritic cell maturation, but in a differential manner. A more mature dendritic cell phenotype could contribute to a more efficient response to infections. Moreover, both fresh and cryopreserved bone marrow-derived dendritic cells can be used as in vitro pre-screening tools which enable an evidence based prediction of the potential immune stimulating effects of different feed additives.


Assuntos
Células da Medula Óssea/imunologia , Células Dendríticas/imunologia , Fatores Imunológicos/farmacologia , Probióticos/farmacologia , Suínos/imunologia , beta-Glucanas/farmacologia , Ração Animal , Animais , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Antígeno B7-2/genética , Antígeno B7-2/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Escherichia coli , Fatores Imunológicos/administração & dosagem , Interleucinas/genética , Interleucinas/metabolismo , Probióticos/administração & dosagem , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , beta-Glucanas/administração & dosagem
10.
Int J Nanomedicine ; 15: 2971-2986, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431496

RESUMO

Background: Due to their extraordinary physical and chemical properties, MoS2 nanosheets (MSNs) are becoming more widely used in nanomedicine. However, their influence on immune systems remains unclear. Materials and Methods: Two few-layered MSNs at sizes of 100-250 nm (S-MSNs) and 400-500 nm (L-MSNs) were used in this study. Bone marrow-derived dendritic cells (DCs) were exposed to both MSNs at different doses (0, 8, 16, 32, 64, 128 µg/mL) for 48 h and subjected to analyses of surface marker expression, cytokine secretion, lymphoid homing and in vivo T cell priming. Results: Different-sized MSNs of all doses did not affect the viability of DCs. The expression of CD40, CD80, CD86 and CCR7 was significantly higher on both S-MSN- and L-MSN-treated DCs at a dose of 128 µg/mL. As the dose of MSN increased, the secretion of IL-12p70 remained unchanged, the secretion of IL-1ß decreased, and the production of TNF-α increased. A significant increase in IL-6 was observed in the 128 µg/mL L-MSN-treated DCs. In particular, MSN treatment dramatically improved the ex vivo movement and in vivo homing ability of both the local resident and blood circulating DCs. Furthermore, the cytoskeleton rearrangement regulated by ROS elevation was responsible for the enhanced homing ability of the MSNs. More robust CD4+ and CD8+ T cell proliferation and activation (characterized by high expression of CD107a, CD69 and ICOS) was observed in mice vaccinated with MSN-treated DCs. Importantly, exposure to MSNs did not interrupt LPS-induced DC activation, homing and T cell priming. Conclusion: Few-layered MSNs ranging from 100 to 500 nm in size could play an immunostimulatory role in enhancing DC maturation, migration and T cell elicitation, making them a good candidate for vaccine adjuvants. Investigation of this study will not only expand the applications of MSNs and other new transition metal dichalcogenides (TMDCs) but also shed light on the in vivo immune-risk evaluation of MSN-based nanomaterials.


Assuntos
Diferenciação Celular , Movimento Celular , Células Dendríticas/citologia , Células Dendríticas/imunologia , Dissulfetos/farmacologia , Molibdênio/farmacologia , Nanopartículas/química , Linfócitos T/citologia , Linfócitos T/imunologia , Animais , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Células Dendríticas/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Nanopartículas/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T/efeitos dos fármacos
11.
Mol Immunol ; 123: 1-6, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380279

RESUMO

The repertoire of dendritic cells (DCs), monocytes and macrophages in adult humans is diverse and we are appreciating this to a greater extent as high throughput methods, such a single-cell RNA sequencing, become widely adopted and scalable. This powerful lens of analysis is also beginning to shed light on prenatal immunology, allowing us to chart the emergence, tissue distribution and developmental regulation of DCs, monocytes and macrophages during early human life. In this review, we will integrate recent insights from studies of the developing immune system into our understanding of adult DC, monocyte and macrophage organization, illustrating where insights from early life both affirm and challenge current understanding.


Assuntos
Células Dendríticas/citologia , Desenvolvimento Fetal/fisiologia , Macrófagos/citologia , Monócitos/citologia , Mielopoese/fisiologia , Análise de Célula Única/métodos , Adulto , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Células Cultivadas , Células Dendríticas/fisiologia , Feminino , Humanos , Macrófagos/fisiologia , Monócitos/fisiologia , Gravidez
12.
Mol Immunol ; 123: 40-59, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32413788

RESUMO

Dendritic cells (DCs) are mononuclear phagocytes that are specialized in the induction and functional polarization of effector lymphocytes, thus orchestrating immune defenses against infections and cancer. The population of DC encompasses distinct cell types that vary in their efficacy for complementary functions and are thus likely involved in defending the body against different threats. Plasmacytoid DCs specialize in the production of high levels of the antiviral cytokines type I interferons. Type 1 conventional DCs (cDC1s) excel in the activation of cytotoxic CD8+ T cells (CTLs) which are critical for defense against cancer and infections by intracellular pathogens. Type 2 conventional DCs (cDC2s) prime helper CD4+ T cells for the production of type 2 cytokines underpinning immune defenses against worms or of IL-17 promoting control of infections by extracellular bacteria or fungi. Hence, clinically manipulating the development and functions of DC types could have a major impact for improving treatments against many diseases. However, the rarity and fragility of human DC types is impeding advancement towards this goal. To overcome this roadblock, major efforts are ongoing to generate in vitro large numbers of distinct human DC types. We review here the current state of this research field, emphasizing recent breakthrough and proposing future priorities. We also pinpoint the necessity to develop a consensus nomenclature and rigorous methodologies to ensure proper identification and characterization of human DC types. Finally, we elaborate on how faithful in vitro models of human DC types can accelerate our understanding of the biology of these cells and the engineering of next generation vaccines or immunotherapies against viral infections or cancer.


Assuntos
Células Dendríticas/citologia , Células Dendríticas/fisiologia , Modelos Teóricos , Animais , Apresentação do Antígeno/fisiologia , Linfócitos T CD8-Positivos/imunologia , Citocinas/metabolismo , Células Dendríticas/patologia , Humanos , Ativação Linfocitária , Reprodutibilidade dos Testes
13.
Nat Rev Nephrol ; 16(7): 391-407, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32372062

RESUMO

Dendritic cells (DCs) are chief inducers of adaptive immunity and regulate local inflammatory responses across the body. Together with macrophages, the other main type of mononuclear phagocyte, DCs constitute the most abundant component of the intrarenal immune system. This network of functionally specialized immune cells constantly surveys its microenvironment for signs of injury or infection, which trigger the initiation of an immune response. In the healthy kidney, DCs coordinate effective immune responses, for example, by recruiting neutrophils for bacterial clearance in pyelonephritis. The pro-inflammatory actions of DCs can, however, also contribute to tissue damage in various types of acute kidney injury and chronic glomerulonephritis, as DCs recruit and activate effector T cells, which release toxic mediators and maintain tubulointerstitial immune infiltrates. These actions are counterbalanced by DC subsets that promote the activation and maintenance of regulatory T cells to support resolution of the immune response and allow kidney repair. Several studies have investigated the multiple roles for DCs in kidney homeostasis and disease, but it has become clear that current tools and subset markers are not sufficient to accurately distinguish DCs from macrophages. Multidimensional transcriptomic analysis studies promise to improve mononuclear phagocyte classification and provide a clearer view of DC ontogeny and subsets.


Assuntos
Lesão Renal Aguda/imunologia , Células Dendríticas/imunologia , Glomerulonefrite/imunologia , Inflamação/imunologia , Rim/imunologia , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Perfilação da Expressão Gênica , Humanos , Rim/citologia , Ativação Linfocitária/imunologia , Macrófagos/imunologia , Neutrófilos/imunologia , Pielonefrite/imunologia , Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia
15.
Stem Cells Dev ; 29(11): 679-681, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: covidwho-60278

RESUMO

The novel coronavirus disease 2019 (COVID-19) has grown to be a global public-health emergency since patients were first detected in Wuhan, China, in December 2019. As of April 9, 2020, the novel coronavirus (named as SARS-CoV-2 by the International Committee on Taxonomy of Viruses on February 11) has infected 83,251 and 1,484,811 patients in China and the world, respectively. However, we have neither confirmed effective antiviral medications nor vaccines available to deal with this emergency. In this commentary, we offer an alternative promising therapy for COVID-19, that is, mesenchymal stem cell transplantation.


Assuntos
Betacoronavirus/imunologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Infecções por Coronavirus/terapia , Células Dendríticas/imunologia , Transplante de Células-Tronco Mesenquimais/métodos , Pneumonia Viral/terapia , Diferenciação Celular/fisiologia , Células Dendríticas/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Pandemias
16.
Nat Biomed Eng ; 4(5): 518-530, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32313101

RESUMO

The detection and quantification of low-abundance molecular biomarkers in biological samples is challenging. Here, we show that a plasmonic nanoscale construct serving as an 'add-on' label for a broad range of bioassays improves their signal-to-noise ratio and dynamic range without altering their workflow and readout devices. The plasmonic construct consists of a bovine serum albumin scaffold with approximately 210 IRDye 800CW fluorophores (with a fluorescence intensity approximately 6,700-fold that of a single 800CW fluorophore), a polymer-coated gold nanorod acting as a plasmonic antenna and biotin as a high-affinity biorecognition element. Its emission wavelength can be tuned over the visible and near-infrared spectral regions by modifying its size, shape and composition. It improves the limit of detection in fluorescence-linked immunosorbent assays by up to 4,750-fold and is compatible with multiplexed bead-based immunoassays, immunomicroarrays, flow cytometry and immunocytochemistry methods, and it shortens overall assay times (to 20 min) and lowers sample volumes, as shown for the detection of a pro-inflammatory cytokine in mouse interstitial fluid and of urinary biomarkers in patient samples.


Assuntos
Bioensaio/métodos , Corantes Fluorescentes/química , Nanopartículas/química , Animais , Células da Medula Óssea/citologia , Linhagem Celular Tumoral , Coloides/química , Células Dendríticas/citologia , Feminino , Citometria de Fluxo , Fluorescência , Humanos , Imunoensaio , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Microesferas , Proteômica , Padrões de Referência
17.
Nat Commun ; 11(1): 2054, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32345968

RESUMO

Classical dendritic cells (cDCs) are rare sentinel cells specialized in the regulation of adaptive immunity. Modeling cDC development is crucial to study cDCs and harness their therapeutic potential. Here we address whether cDCs could differentiate in response to trophic cues delivered by mesenchymal components of the hematopoietic niche. We find that mesenchymal stromal cells engineered to express membrane-bound FLT3L and stem cell factor (SCF) together with CXCL12 induce the specification of human cDCs from CD34+ hematopoietic stem and progenitor cells (HSPCs). Engraftment of engineered mesenchymal stromal cells (eMSCs) together with CD34+ HSPCs creates an in vivo synthetic niche in the dermis of immunodeficient mice driving the differentiation of cDCs and CD123+AXL+CD327+ pre/AS-DCs. cDC2s generated in vivo display higher levels of resemblance with human blood cDCs unattained by in vitro-generated subsets. Altogether, eMSCs provide a unique platform recapitulating the full spectrum of cDC subsets enabling their functional characterization in vivo.


Assuntos
Células Dendríticas/citologia , Nicho de Células-Tronco , Animais , Biomarcadores/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Quimiocina CXCL12/farmacologia , Análise por Conglomerados , Colágeno/farmacologia , Células Dendríticas/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Laminina/farmacologia , Proteínas de Membrana/metabolismo , Camundongos , Organoides/efeitos dos fármacos , Organoides/metabolismo , Proteoglicanas/farmacologia , Nicho de Células-Tronco/efeitos dos fármacos , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo
19.
Stem Cells Dev ; 29(11): 679-681, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32292113

RESUMO

The novel coronavirus disease 2019 (COVID-19) has grown to be a global public-health emergency since patients were first detected in Wuhan, China, in December 2019. As of April 9, 2020, the novel coronavirus (named as SARS-CoV-2 by the International Committee on Taxonomy of Viruses on February 11) has infected 83,251 and 1,484,811 patients in China and the world, respectively. However, we have neither confirmed effective antiviral medications nor vaccines available to deal with this emergency. In this commentary, we offer an alternative promising therapy for COVID-19, that is, mesenchymal stem cell transplantation.


Assuntos
Betacoronavirus/imunologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Infecções por Coronavirus/terapia , Células Dendríticas/imunologia , Transplante de Células-Tronco Mesenquimais/métodos , Pneumonia Viral/terapia , Diferenciação Celular/fisiologia , Células Dendríticas/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Pandemias
20.
Artigo em Chinês | MEDLINE | ID: mdl-32314717

RESUMO

Objective To investigate the effect of hydroxychloroquine (HCQ) on 5-fluorouracil (5-FU)-induced enteritis in mice and its mechanism. Methods Thirty C57B6/J mice were randomly divided into 0-, 1-, 3-, 5- and 7-day groups and sacrificed separately at day 0, 1, 3, 5, and 7 after intraperitoneal administration of 5-FU 200 µL/d (50 mg/kg) at day 1-3. The double-stranded DNA (dsDNA) levels in serum and small intestinal fluid were detected by dsDNA quantification kit. Severity of enteritis was evaluated by diarrhea score. HCT-116 cells were cultured in vitro and treated with 5-FU at different concentrations (0, 0.01, 0.1, 0.5, 1, 10 µmol/L) for 72 hours or 5-FU at 1 µmol/L for different time (24, 48, 72 hours). The dsDNA concentration in the cell culture supernatant of each group was detected by dsDNA quantification kit. Twenty-four C57B6/J mice were randomly divided into 4 groups: control group (intraperitoneal injection and intragastric administration of 200 µL/d saline), model group (intraperitoneal injection of 50 mg/kg 5-FU of 200 µL/d, intragastric administration of saline 200 µL/d), HCQ treatment group (intragastric administration of 60 mg/kg HCQ of 200 µL/d, starting at 1 day before the first intraperitoneal injection of 50 mg/kg 5-FU of 200 µL/d) and HCQ group (intragastric administration of 60 mg/kg HCQ solution of 200 µL/d). And they were sacrificed after 6 days. Small intestine lesions were observed by HE staining. Apoptotic cells in the small intestine were detected by TUNEL staining. The expression levels of CD11c, Toll-like receptor 9 (TLR9) and nuclear factor κB (NF-κB) in the small intestine were assessed by immunofluorescence staining. Interleukin-1ß (IL-1ß) levels in the serum were detected by ELISA. Mouse bone marrow-derived dendritic cells (BMDCs) were cultured in vitro and stimulated by dsDNA using LipofectamineTM 3000. The expression of TLR9 and NF-κB in BMDCs were detected by Western blotting and immunofluorescent staining, respectively. IL-1ß level in the cell supernatant was detected by ELISA. Results Large amounts of apoptotic cells were observed in the small intestine of 5-FU-treated mice and the dynamic changes of dsDNA levels in the serum and small intestinal lavage fluid were consistent with that of diarrhea score. 5-FU triggered dsDNA release from HCT-116 cells in a dose- and time-dependent manner. HCQ alleviated the destruction in small intestinal epithelium and inhibited the expression levels of TLR9, NF-κB and IL-1ß in the serum. The infiltration of a large number of dendritic cells in the small intestine of model mice was observed. After BMDCs were stimulated with dsDNA, the expression of TLR9, NF-κB, and IL-1ß all significantly increased and HCQ significantly decreased. Conclusion HCQ alleviates 5-FU-induced enteritis in mice and inhibit TLR9 and NF-κB-dependent DNA sensing pathways and the secretion of IL-1ß in dendritic cells.


Assuntos
Enterite/tratamento farmacológico , Fluoruracila/efeitos adversos , Hidroxicloroquina/farmacologia , Animais , Linhagem Celular Tumoral , Células Dendríticas/citologia , Enterite/induzido quimicamente , Humanos , Interleucina-1beta/metabolismo , Intestino Delgado/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Distribuição Aleatória , Receptor Toll-Like 9/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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